Security + Cryptography

A checksum is a hexadecimal value that is computed to verify authenticity. The other values are not hexadecimal values computed to verify authenticity.

Quantum cryptography is a form of encryption that is based on the characteristics of the smallest particles known. Algorithm errors occur when predictable results create a weakness in the coding system. Frequency analysis involves looking at blocks of an encrypted message to determine whether any common patterns exist. Brute-force attacks apply every possible combination of characters until a match is found.

Steganography is the hiding of one message within another. There is no such valid cipher as reverseography. A transposition cipher is one in which characters are scrambled in a certain manner. A substitution cipher is a simple coding system that changes one character or symbol into another.

Symmetric algorithm encryption methods use either a block cipher or a stream cipher.

Hashing is the process of converting a message into a numeric value.

A substitution cipher is a simple coding system that changes one character or symbol into another. There is no such valid cipher as reverseography. Steganography is the hiding of one message within another. A transposition cipher is one in which characters are scrambled in a certain manner.

Message Authentication Code (MAC) is derived from the message and a key and is used to verify integrity of a message. The other choices listed are not valid options.

In the hierarchical model, a root CA at the top provides all the information to intermediate CAs (and they pass it down to leaf CAs). This does not happen in the other models.

The Certificate Revocation List (CRL) is a list of the certificates that are being revoked (usually because they are lost or stolen). The Certificate Practice Statement (CPS) is a statement that that CA uses to issue certificates and implement the policies of the CA. The other choices are not valid for PKI.

The National Institute of Standards and Technology (NIST) was formerly known as the National Bureau of Standards (NBS).

Frequency analysis involves looking at blocks of an encrypted message to determine whether any common patterns exist. Quantum cryptography is a form of encryption that is based on the characteristics of the smallest particles known. Algorithm errors occur when predictable results create a weakness in the coding system. Brute-force attacks apply every possible combination of characters until a match is found.

In a bridge trust model, a peer-to-peer relationship exists between the root CAs. This can also be true in the mesh and hybrid models, but they are not the simplest model in which this happens. In the hierarchical model, a root CA at the top provides all the information to intermediate CAs (and they pass it down to leaf CAs).

MD5 produces a 128-bit hash value.

ECC is based on the idea of using points on a curve to define the public/private key pair. Diffie-Hellman is used for the transmission of keys only. El Gamal is an asymmetric algorithm based on calculating logarithms. RSA uses large integer numbers for the basis of its process.

The update for SHA is the SHA-1 standard.

The most popular version of X.509 is version 3.

Blowfish is a 64-bit block cipher. IDEA was developed by a Swiss consortium and uses a 128-bit algorithm key. CAST was developed by Carlisle Adams and Stafford Tavares and uses a 40-bit to 128-bit key. RC5 uses a key size up to 2,048 bits for symmetric encryption.

The four key components of Public Key Infrastructure (PKI) are certificate authority (CA), registration authority (RA), RSA, and digital certificates.

Algorithm errors occur when predictable results create a weakness in the coding system. Quantum cryptography is a form of encryption that is based on the characteristics of the smallest particles known. Frequency analysis involves looking at blocks of an encrypted message to determine whether any common patterns exist. Brute-force attacks apply every possible combination of characters until a match is found.

The three main categories of cryptography are physical, mathematical, and quantum. Steganography is a form of physical cryptography but not a category of its own.

If security is a real concern on your network, most experts recommend 10 characters as the minimum for password length. They also recommend including as many different character sets as possible.

RSA uses large integer numbers for the basis of its process. ECC is based on the idea of using points on a curve to define the public/private key pair. Diffie-Hellman is used for the transmission of keys only. El Gamal is an asymmetric algorithm based on calculating logarithms.

The Local Registration Authority (LRA) can be used to identify or establish the identity of an individual.

IDEA was developed by a Swiss consortium and uses a 128-bit algorithm key for symmetric encryption. CAST was developed by Carlisle Adams and Stafford Tavares and uses a 40-bit to 128-bit key. Blowfish is a 64-bit block cipher. RC5 uses a key size up to 2,048 bits.

CAST was developed by Carlisle Adams and Stafford Tavares and uses a 40-bit to 128-bit key. IDEA was developed by a Swiss consortium and uses a 128-bit algorithm key. Blowfish is a 64-bit block cipher. RC5 uses a key size up to 2,048 bits for symmetric encryption.

The three most common versions of MDA are MD2, MD4, and MD5.

Secure Hash Algorithm (SHA) produces a 160-bit hash value.

The four main types of trust models used with PKI are hierarchical, bridge, mesh, and hybrid.

The Certificate Practice Statement (CPS) is a statement that the CA uses to issue certificates and implement the policies of the CA. The Certificate Revocation List (CRL) is a list of the certificates that are being revoked (usually because they were lost or stolen). The other choices are not valid for PKI.

Both Diffie-Hellman and El Gamal are asymmetric algorithms based on calculating logarithms. Here's a brief explanation of each:

Diffie-Hellman: This algorithm is a method for securely exchanging cryptographic keys over a public channel, allowing two parties to establish a shared secret key. It is based on the difficulty of calculating discrete logarithms.

El Gamal: This algorithm is used for public key encryption and digital signatures. It is based on the difficulty of solving the discrete logarithm problem and is an extension of the Diffie-Hellman key exchange.

RSA, while also an asymmetric algorithm, relies on the difficulty of factoring large prime numbers, not logarithms. ECC (Elliptic Curve Cryptography) is another asymmetric algorithm that is based on the algebraic structure of elliptic curves over finite fields.